MTBF-calculation-basis

RELIABILITYCALCULATIONFROMHI-RELDATA========================================PARTNO:xxxxxDATASOURCE:========================================================Thefollowingfailureratecalculationisbasedonthe:-ARRHENIUSEQUATIONFORACCELERATIONFACTOR(AF)wherexAF=e,wherex=EA/k(1/TN-1/TA)TN(OPERATINGTEMP))=55°CNormal:50oCto55oCTA(ACCELERATEDTJ)=150°C.............HTRBTA(ACCELERATEDTJ)=150°C..........OPLIFEACTIVATIONENERGY=1eVCONFIDENCELEVEL=60%(60%or90%)Normal:60%ACCELERATIONFACTOR(1)=2804.4186ACCELERATIONFACTOR(2)=2804.4186andfailurerateiscalculatedusingchisquaredistribution.FAILURERATE=CHI(SQUARED)/(2xTOTALDEVICEHOURS)2CHI(SQUARED)=1/2(U+SQRT{2(2R+2)-1})U=0.25FOR90%CONFIDENCE60%CONFIDENCEThusforxxxxxatTj=55°C============(1)HTRBTOTALHOURSATTJ(ACC)=77000150°C)(N*H)TOTALHOURSATTJ(OPERATING)=21594022955°C)(2)OPLIFETOTALHOURSATTJ(ACC)=77000150°C)(N*H)TOTALHOURSATTJ(OPERATING)=21594022955°C)TOTALHRSATTJ(OPERATING)(1)+(2)=431880457TOTALREJECTS-PARAMETRIC(D)(D)=0TOTALREJECTS-OPEN/SHORT(C)=1CHI(SQUARED)-D=1.9660%CONFIDENCE)CHI(SQUARED)-C=4.1960%CONFIDENCE)..................................................................FAILURERATEAT60%:CONFIDENCE-PARAMETRIC=2(FIT)ATTj:DEGRADATION===========55°C:........................................................................:..................................................................FAILURERATEAT60%:CONFIDENCE-TOINOPERATIVE=4.9(FIT)ATTj:(OPEN/SHORT)FAILURE==========55°C:........................................................................:MTBF(Inoperativefailure)=2.06E+08HRS==================================================MTBF(Inoperativefailure)=23,518YRS==================================================